The mesocolon retains its primitive attachment to the median line ventrad of the large prevertebral blood vessels.
The mesentery and mesocolon are seen in a similar condition, causing wrinkling and shortening of the bowels.
The adhesion, which in the human subject fuses this layer with the transverse colon and mesocolon, does not occur in the monkey.
Adhesion of the mesocolon to the dorsal body wall (parietal peritoneum) does not occur at all points at the same time.
Fig. 549 shows the arrangement in unimpeded ccal descent without adhesion of colon and mesocolon to the parietal peritoneum.
In 14 a mesocolon was found in both the ascending and descending segments of the large intestine.
Hence from this series a mesocolon may be expected on the left side in 36 per cent., on the right side in 26 per cent.
On the left: right layer of mesocolon (secondary lumbar parietal peritoneum in the adult human subject).
The great omentum is not yet adherent to the transverse colon and mesocolon except for a short distance on the extreme right.
Tracing the omentum dorsad beyond the transverse colon and mesocolon the pancreas is reached.
mesocolon mes·o·co·lon (měz'ə-kō'lən, měs'-)
The fold of peritoneum attaching the colon to the posterior abdominal wall.